There has been well known a fluid control device comprising a valve case having a fluid channel, a casing provided above the valve case, a valve element opening and closing the fluid channel, a valve element holder moved between a closing position at which it is moved downward to set the valve element in a closed state and an opening position at which it is moved upward to set the valve element in an open state, an elastic member biasing the valve element to the closing position or the opening position, and a working member in automatic opening and closing which is vertically moved by automatically opening and closing means to move the valve element holder to the opening position or the closing position against force of the elastic member (Patent Document 1: the publication of JP-A No. 2000-283328). The fluid control device disclosed in Patent Document 1 is of an automatic type (automatic valve) which automatically moves a valve stem serving as an working member in automatic opening and closing using compressed air. However, there has also been well known a manual fluid control device (manual valve) which manually moves a valve stem serving as a working member in manual opening and closing by turning an operation handle.
The above conventional automatic valve and manual valve are generally combined to constitute an opening and closing mechanism. In its normal use state, a fluid channel is controlled by closing and opening operation of the automatic valve while the manual valve is in an open state and when it becomes necessary to shut off the fluid channel in the event of an emergency, an operator operates the manual valve. Thus, to use both automatic valve and manual valve wastes cost and space.
It is an object of the present invention to provide a fluid control device having both functions as a manual valve and an automatic valve in which a conventional opening and closing mechanism comprising the automatic valve and the manual valve can be replaced with one control device.